Q 11-10-031NEETJEE MainEAMCET 2003 (Medical)Easy
A particular star (assuming it to be a black body) has a surface temperature of about $5 \times 10^4$ K. The wavelength in nanometres at which its radiation becomes maximum is ($b = 0.0029$ m K)
Answer: (B) $58$
Concept. Wien's displacement law: $\lambda_m = \dfrac{b}{T}$.
Step 1. Substitute.
$$\lambda_m = \frac{0.0029}{5 \times 10^4} = 5.8 \times 10^{-8}\ \text{m} = 58\ \text{nm}$$
Answer. $58$ (Option B).
Solution by Sreeraj P, M.Sc Physics